Exhaust aftertreatment systems are used to receive and treat exhaust gas generated by engines (e.g., IC engines). Conventional exhaust gas aftertreatment systems include any of several different components to reduce the levels of harmful exhaust emissions present in exhaust gas. For example, certain exhaust aftertreatment systems for diesel-powered IC engines include a selective catalytic reduction (SCR) system to convert NOx (NO and NO2 in some fraction) into harmless nitrogen gas (N2) and water vapor (H2O) in the presence of ammonia (NH3). Generally in such conventional aftertreatment systems, a reductant, (e.g., a diesel exhaust fluid such as urea) is injected into the aftertreatment system. The reductant is allowed to mix with the exhaust gas and facilitates decomposition of constituents of the exhaust gas by a catalyst included in the SCR system.
Conventional aftertreatment systems include an injector configured to insert the reductant into the aftertreatment system. The reductant can deposit on inner surfaces of the sidewall of a housing of the aftertreatment system which can increase exhaust gas backpressures, clog nozzles and/or components of the exhaust system and eventually lead to reduction in a catalytic conversion efficiency of the aftertreatment system. Furthermore, particulate matter such as soot, carbon particles and debris can also deposit on the inner surface of the sidewalls of the housing.